My advice is the same as the others, except this:
If the shop is nearby (and that would be your idea of "nearby"

, do the shop this week - preferably today. Submit your report with a comment in the comment section that "due to the traffic conditions, the shop could not be completed in the required time period".
But, first, before going out to perform the shop, go to the shop's online report section (btw, it should have an "overdue" notice) and click on the link to submit the report. Enter the access code and then see if it allows you to enter information. If it does, click on the "save" link and perform the shop.
I like Maritz because they are understanding and only wish to get their reports done/not punish.
Last of all, I would followup with a telephone call - no Emails. Also, I wouldn't perform the shop if for some reason, you would incur any great expense that would be reimbursed.