I don't know where to start with this. Long story I travel around NZ for work. We have had some new rules put in place regarding exactly when we do these trips. IE how close to date, and day of week they were done last time etc.

For the last few years I've done this in excel, basically subtracting the date from the month before, it spits out a number and I know if we are ok, or need to move it. However we have some extra compliance that we need to meet, and I don't know where to start with it. Fitting mine and my colleagues trips in each month is a bit like tetris, some are three days, some are four, some are five. So we have to balance that as well. Plus any leave, or regional holidays etc.

Is there software or excel sheets that can take some of the manual labour out of this? IE smart enough to look up say a cell called Wellington, and it can then place it in the following month according to some set rules?

I'm not even sure what to google for this!