Google sheets join arrays

Question

What I'm trying to do is to join few arrays of dates.

For start, I have start date and amount of months I want to generate. Which I did by using =ARRAYFORMULA(DATE(YEAR(A2), MONTH(A2) + SEQUENCE(C2, 1, 0, 1), 1)) formula, where A2 is start date and C2 is amount of months to generate.

Formula I cannot come up to is to do same for all existing rows and join all generated arrays of dates in a single column.

Also, I'd like to copy some columns next to every date to identify from which row it is. I have done this by formula =TRANSPOSE(SPLIT(JOIN(",", ARRAYFORMULA(REPT(SPLIT(D2,",")&",", C2))), ",")) which I found in google.

Also, here is what I have reached so far and you can test your versions too.

Sample

Answer 1

It just combines these formulas, so if you need to add some more data - have to do it manualy

={ TRANSPOSE(SPLIT(JOIN(",",ARRAYFORMULA(REPT(D2&",", C2))), ",")), 
ARRAYFORMULA(DATE(YEAR(A2), MONTH(A2) + SEQUENCE(C2, 1, 0, 1), 1));
TRANSPOSE(SPLIT(JOIN(",",ARRAYFORMULA(REPT(D3&",", C3))), ",")),
ARRAYFORMULA(DATE(YEAR(A3), MONTH(A3) + SEQUENCE(C3, 1, 0, 1), 1));
TRANSPOSE(SPLIT(JOIN(",",ARRAYFORMULA(REPT(D4&",", C4))), ",")),
ARRAYFORMULA(DATE(YEAR(A4), MONTH(A4) + SEQUENCE(C4, 1, 0, 1), 1));
TRANSPOSE(SPLIT(JOIN(",",ARRAYFORMULA(REPT(D5&",", C5))), ",")),
ARRAYFORMULA(DATE(YEAR(A5), MONTH(A5) + SEQUENCE(C5, 1, 0, 1), 1)) }