LOR all at once?

[HowDidIGetHere]

So only one of my LOR have been submitted to interfolio so far. Should I just send them out as they come in or wait to send them all at once?

Thanks

 

[guylewis]

great question and I'd like to know this as well since I'm sitting on 7 secondaries at the moment while waiting for my science prof to get back from her vacation to write me this necessary letter

 

[HowDidIGetHere]

I'm waiting on two letters that are at least a month overdue.