Do People Per Hour have an SLA which Freelancers must Use?

I have posted a number of Projects on PPH and whilst I have found a certain degree of satisfaction the most common issue I have with nearly all Freelancers is that they are overtrading.  I would appreciate if PPH could make this point to Freelancers as it always leads to unacceptable delays in Project Completions for Buyers. Too many Freelancers are accepting Projects which they are unable to process on time because of their overload of Projects or other work they have taken on. I have a current PPH Project which was a relatively straightforward Wordpress website which is now nearly two months overdue. This delay is caused entirely  because the Freelancer has taken on more work than he can honestly deal with.

If PPH do not provide a reasonable SLA which Freelancers must agree to then could I please put this forward as a suggestion for them to do so.