not sure i believe it varies on they type of alteration and possible whether that particular gm is on duty, vacation etc.
you may wish to try to resubmit your scroll by copying the design and reputting on the scroll.
i am not sure if you can contact the gm personally but if you dont get any type of reply you could possibly contact Simu and ask to speak to someone in regards to LTB alteration scrolls and explain what is going/or has gone on and see if they can do anything.
sorry i can not be of more help here.
i know that alteration i had done took awhile as well but it did get done eventually.
morgy