Hi,
In the example the timer interrupt period is significantly longer than the time required to process the interrupt, so the order of those operations does not matter. In more complex designs where you want to prevent interrupts from re-firing while the old one is still processed, you may want to use various configuration registers of the interrupt controller (e.g. BASEPRI).
Regarding support times, the forum is moderated by sysprogs, however unlike the email support, it’s mostly suited for general discussions rather than urgent/blocking issues. Requests that require external research sometimes take longer to answer. For email requests our policy is to provide an answer within 48 hours, however the average time is less than 12 hours (depending on the time zone).