The .htaccess file seems completely unrelated to the front-end backup issue. I see that it terminates suspiciously close to 960 seconds, without an error. In fact, the step is complete and it returns successfully. However, the remote end does not try to execute the next step. I suspect that your real problem is that the CRON job has a hard time limit between 950 and 960 seconds. When it goes over it, the CRON job is killed. Since the actual backup step already running is NOT part of the CRON job process[1] it runs to completion. But since the CRON job is dead the next step cannot run.
Note 1: This has to do with the way operating systems handle processes. The CRON job process accesses a special URL to step through the backup. Whenever it accesses that URL, a new web server process is spawned to handle it. This new process does not belong to the CRON job process. Therefore, when the system kills the CRON job process the other (web server) process is not killed.
The solution is to ask your CRON job host to give you more time to run it.
Nicholas K. Dionysopoulos
Lead Developer and Director
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