They have already broken it but so far it was "small enough" that Iran didn't retaliate.
In a better world Iran would get a massive emergency delivery of AA systems and would take any small incursion by drones to pummel the colonists back to the stone age, specially around Gaza. But I'm not expecting the resumement of hostilities to go so well.
Any lack of retaliation will be seen as a green light for more attacks and even the yanks are likely to join in. Any retaliation will also result in more attacks but at least this way Iran can reduce the colonists capabilities which they will inevitably have to do.
The question is, will waiting to attack favour Iran or the imperialists?
If Iran can get new military gear (like from China,) but only during the "truce", reorganize and root out traitors then waiting a while may be the best move, but they don't have forever for that.