The Sabbaths of the Torah which were shadows of things to come

Colossians 2:16-17 EMTV

(16)  Therefore do not let anyone judge you in food or in drink, or regarding a festival or of a new moon or of sabbaths, (17)  which are a shadow of things to come, but the body is of Christ.

There are 5 festivals in addition to the rest from work of the seventh day where cessation from work was obligated

[Sabbath only implies no servile work]

We read in Leviticus 23, the various occasions when God called off work for sabbaths

Leviticus 23:1-2 ASV

(1)  And Jehovah spake unto Moses, saying,

(2)  Speak unto the children of Israel, and say unto them, The set feasts of Jehovah, which ye shall proclaim to be holy convocations, even these are my set feasts.

From that Sunday of the firstfruits, the Jews were to count seven Sabbaths adding to 49 days to the last Sabbath and the 50th day, necessarily a Sunday, was a festival with a holy convocation.

Pentecostal Sunday was a Jewish Sabbath (rest) day with a holy convocation

And ye shall make proclamation on the selfsame day; there shall be a holy convocation unto you; ye shall do no servile work: it is a statute for ever in all your dwellings throughout your generations.  (Leviticus 23:21 ASV)

The Feast of the 7 Sabbaths were to be celebrated in Jerusalem not in Israel, as almost if not all the feasts. Outside of Jerusalem, or none of the ordinances were allowed to be carried out. That was why the Jews went to Jerusalem to observe the ordinances. The observance of the seventh day Sabbath was not restricted to only Jerusalem or Israel. That is one of the reason Paul was not calling for its abolishment.

And you shall rejoice before Jehovah your God, you and your son, and your daughter, and your male slave, and your slave-girl, and the Levite that is inside your gates, and the alien, and the fatherless, and the widow that are among you, in the place which Jehovah your God shall choose to cause His name to dwell there.  (Deuteronomy 16:11 LITV)

Note that the Pentecostal day, even though it was a Sabbath, was a day to rejoice. That is besides not working, the Jews were permitted to carry on activities to enjoy themselves. 

Leviticus 23:23-25 ASV

(23)  And Jehovah spake unto Moses, saying,

(24)  Speak unto the children of Israel, saying, In the seventh month, on the first day of the month, shall be a solemn rest unto you, a memorial of blowing of trumpets, a holy convocation.

(25)  Ye shall do no servile work; and ye shall offer an offering made by fire unto Jehovah.

Leviticus 23:26-28 ASV

(26)  And Jehovah spake unto Moses, saying,

(27)  Howbeit on the tenth day of this seventh month is the day of atonement: it shall be a holy convocation unto you, and ye shall afflict your souls; and ye shall offer an offering made by fire unto Jehovah.

(28)  And ye shall do no manner of work in that same day; for it is a day of atonement, to make atonement for you before Jehovah your God.

Thou shalt keep for thyself the feast of tabernacles seven days, when thou gatherest in thy produce from thy corn-floor and thy wine-press.  (Deuteronomy 16:13 Brenton)

The feast of tabernacles or booths was instituted as days for everyone to rejoice

And thou shalt rejoice in thy feast, thou, and thy son, and thy daughter, thy man-servant, and thy maid-servant, and the Levite, and the stranger, and the orphan, and the widow that is in thy cities.  (Deuteronomy 16:14 Brenton)

The 1st day, that is the 15th of the 7th month, was a Sabbath day with a holy convocation.

And on the first day shall be a holy convocation; ye shall do no servile work.  (Leviticus 23:35 Brenton)

The 8th day, that is the 22nd of the 7th month, was a Sabbath day with a holy convocation

Seven days shall ye offer whole-burnt-offerings to the Lord, and the eighth-day shall be a holy convocation to you; and ye shall offer whole-burnt-offerings to the Lord: it is a time of release, ye shall do no servile work.  (Leviticus 23:36 Brenton)

The feast was to be observed all over Israel

Seven days ye shall dwell in tabernacles: every native in Israel shall dwell in tents,  (Leviticus 23:42 Brenton)

The Law was to be read to all every 7 years during the festivities of the Tabernacles

Deuteronomy 31:9-13 Brenton

(9)  And Moses wrote the words of this law in a book, and gave it to the priests the sons of Levi who bear the ark of the covenant of the Lord, and to the elders of the sons of Israel.

(10)  And Moses charged them in that day, saying, After seven years, in the time of the year of release, in the feast of tabernacles,

(11)  when all Israel come together to appear before the Lord your God, in the place which the Lord shall choose, ye shall read this law before all Israel in their ears,

(12)  having assembled the people, the men, and the women, and the children, and the stranger that is in your cities, that they may hear, and that they may learn to fear the Lord your God; and they shall hearken to do all the words of this law.

(13)  And their sons who have not known shall hear, and shall learn to fear the Lord thy God all the days that they live upon the land, into which ye go over Jordan to inherit it.

To recap

Thus, the Jews were obligated to keep a total of 8 sabbaths (no servile work to be done). During those days of rest, they were to carry out ceremonial activities including animal sacrifices among other things. Those Sabbath (rest) days (except the seventh day sabbath and Pentecostal day) could fall on any day of the week, even on the 7th day, according to the dates of the chosen months, unless the Jews decided otherwise for their convenience in tweaking their months. 

It is worth noting that the seventh day rest, being unique, even though it made the list of Leviticus 23, does not call for any accompanying ceremonial ordinances, not having ever been a shadow.

Therefore, the seventh day rest is not included in Colossians 2:16-17 as Sabbaths fulfilled by the sacrifice and offering of the body of Jesus.

the Sunday Pentecostal Sabbath

As you might have realized 1 of the Sabbath days of the feasts of Leviticus 23 fell on Sundays, the 50th day after the counting of 7 Sabbaths. 

Therefore, if the Sabbatical nature of the day of Pentecost floated around as the reason to have called for Sunday as a Sabbath day, the verses Colossians 2:16-17 of the New Testament that speak of the ordinances that were but shadows to come (thus obsolete), invalidate any attempt to make Sunday a replacement for Saturday in term of Sabbath (rest).

 As it is written:

For we cannot have any power against the truth, but on behalf of the truth. (2 Corinthians 13:8 KJ3)

because the word of God is used to

2 Timothy 3:16-17 KJ3

(16)  All Scripture is God-breathed and profitable for doctrine, for reproof, for correction, for instruction in righteousness,

(17)  so that the man of God may be complete, having been fully equipped for every good work.

The Jewish Months and the sabbaths of shadow

In researching the sabbaths of the Scriptures in order to fully understand the abolishment of sabbaths, festival, or new moon advocated in Colossians 2:16-17 because those ordinances were shadows of things to come, you may notice that there are at least 2 ordinances that always fall on a Sunday and were considered sabbath day because servile work in them was forbidden. Moreover, in each of those sabbaths, except the sabbath of the seventh day, there were ceremonial activities to be carried in the Temple. The Temple is no more, so, besides being shadows and agricultural, those ordinances cannot be performed legally according to Moses. There is no guidance in the Scripture for the resurgence of the Temple with its ceremonial activities after its final destruction.

The seventh day Sabbath is not within the scope of Colossians 2:16-17

All the teachings against the observance of the Law as obsolete have only one target the abolishment of the seventh day and its requirements. However, the biblical authority to discard the seventh day is lacking because the biblical support exhibited against the seventh day has nothing to do with with the seventh day. The seventh day was instituted from the creation of our life, independent of any nation or anything that was a shadow to come.

The effort is to make Sunday instead of established Saturday the day of worship. Unfortunately, the word "sabbaths", which is used for the so-called abolishment of the Saturday sabbath in the New Testament, also includes Sunday as a sabbath day. Therefore, if the passages do call for abolishing sabbaths, not a day, even Sunday sabbath can be considered because all the days of the week had become a temporary candidate to host a day of Sabbath (rest).