Is there any limitations set for moving between day and night shift work, for example: doing four nights on four nights off for a month, then doing six days on two days off for a month then switching back to nights.

Not sure at what point the two become untenable together or if this type of mixing shifts can only be done for short periods of tim or a one off in expectional circumstance.

https://www.acas.org.uk/working-time-rules/night-workers

Working Time Directive discusses a minimum uninterrupted 11 hour break between work periods.

Slightly different rules for night workers (see hyperlink)

In a previous existence once a year we worked a double back (rota gave 10 day maximum break so in summer we would finish nights at 06:00 and come back in at 14:00 to cover another shifts afternoons so we all got 14 consecutive days) - it was rightly named the zombie shift - back then weekend involved 12 hour days / 12 hour nights (or 11 & 13 at clock change).