Is it possible to delete days already booked if one returns from vacation early?

Yes.

>Vacations that are yet to start can be cancelled simply by clicking them.

>All vacations are booked using GMT which may not match your time zone precisely.

I am aware that one can cancel a vacation that has not started, my question is if I have booked 2 weeks vacation and I return after 1 week is it posssible to annulate the second week?

Yes. Any vacation days that have yet to be used can be deleted and will not count against you. Click the day or days you wish to cancel. Note that GMT, if different from your own, may affect how many days you can cancel.

Thanks but I am unable to delete as you suggest. If I book another vacation I can remove it as you say, but am unable to delete a vacation that has already started in the same way.

I think that is because it doesn't actually update until midnight (GMT) so you will still be shown on holiday until then. The subsequent unused days will be cancelled and put back in your annual allowance.

I added a vacation day for July, then came back a few minutes later and successfully deleted it. Are you trying to delete today or tomorrow's date? That is where you run into trouble with GMT; the RHP computer thinks it's tomorrow, while at your location you're still living in today.

OK I have found the solution. You do not click on the days that you wish to cancel, that does not work. On the left hand side of the page at the top of the column you click on cancel vacation and it cancels the rest of the booked vacation.

How can I mark a vacation on my games when I go away for a week

Go to MySettings>MyVacationSettings and fill in your booking dates. Don't forget to allow for timezone differences, otherwise your vacation protection might end earlier or later than you intended.