Bush pilot...nothing. In fact best to keep doing it. That practice hails back to the days when everyone flew full reporting with the requirement to give an estimate for each reporting point/destination + or- 2 minutes and before GPS was invented. These days most have GPS therefore arrival time can be given exactley. Problem is most of the drivers tooling around today know no different so estimates are a bit confusing for them.
Ofcourse I could throw in a mention of the old AFIZ and really confound them
So long as other drivers in the circuit know when and what direction you are arriving from that's fine.