In the mean time, can you hint me to what API function(s) will you use to initiate a withdrawal request.
Also, for the recurring functionality, do you intend using crontab or own calendar/timer?
This request still remains wide open for offers
For the withdrawal request, one option is mentioned on https://en.bitcoin.it/wiki/MtGox/API/HTTP/v0#0.2Fwithdraw.php
0/withdraw.php
withdraw / Send BTC
To make a withdraw in another Currency , use group1=USD2CODE and add a Currency parameter ( example Currency=EUR to get a mtgox EUR coupon )
One very simple approach is to have a human readable list of days of the month that you wish to autowithdraw. (e.g. 10th, 25th) and to make the script a one-shot that re-schedules itself at the next desired time.
I usually think of PHP as event driven on a server, not schedule driven from a client. The crontab job could be a tiny web client that just pulls a certain URI from your server running the PHP script.