On a different note, if your IFR deptarting from an OCTA aerdrome you of course dont need a clearance (unless your going to Class A, then you just need it before you get there).
Many times I have been at a community airstrip and departed without a taxi call becaseu HF is having another bad day, with the intention of contacting CN once airborne. Perfectly fine, as long as you remember that without the taxi call nobody knows you have departed so if you spud it in after take off nobodys going to come looking for you.....
In which case you should file a SARTIME for departure
