24x7 Roster - 12h shifts - 8 staff

Hi guys, I am new to the forum. Did I say hi? Hi!

I have looked through the forums and I understand that every case should be opened in a different thread, at least for roster spread sheets, as they vary greatly from one to another.

Basically we are 8 guys who need to work in a 24x7 schedule, 12 h per shift, 2 guys per shift, a maximum of 4 consecutive shifts and, if possible, only having to work 1 out of every 4 weekends (Sat/Sun). The amount of day shifts (08:00 - 20:00) and night shifts (20:00 - 08:00) should be assigned equally among us 8, with around a 36% of shifts being night shifts. We have already a 12 weeks rota spread sheet working for 6 (see attached) and we would like to adapt it/modify it (it does not have to be a 12 weeks rota) so we can fit 8 guys in it and with a minimum of 2 guys per shift.

Note that in the attached spreadsheet, NOC1 and NOC2 should be treated as one (Day shift), so for instance, in Week1, Monday and Tuesday have 1 guy only during the day, Wednesday and Thursday 3 guys, Friday 2, etc.

Thank you so much in advance for your help, any help appreciated.

All the best,

Nico