I think Tesla is now pretty sure to be profitable each quarter going forward. Combined with production and deliveries going up probably 10% on average each quarter they may start to care less about deliveries slipping a quarter. At least for smallish shipments.
With 200k cars each quarter now, 2k cars is only 1%. Now they have 2k (or whatever number) extra in Q3. Or they can do it again at the end of Q3 and let some slip over into Q4.
As production grows this will be less and less of a problem.
As for the smaller ships, wasn't there talk recently about a problem securing ships out of some ports? Or was that only because of Covid concerns in those ports, not actual lack of ships?
Either way. If there was a problem getting enough of the regular ships that might actually be another reason to send some early to avoid a problem getting all exports shipped before end of Q3.
Also, the youtube videos from the last week of Q2 did show a huge number of cars that seemed to be meant for export. This was kind of in doubt then, for the same reason you bring up - that was not how Tesla normally did it, but it fits well with this ship leaving on July 3.