Patrick, sorry for the delay in getting back to you.
It's 50/50 whether to retake the IELTS. You're likely to be invited within 4-6 weeks I'd have thought. Retaking IELTS will guarantee an invitation on the next round, but you'll still have to wait 2 weeks for a result, so it's swings and roundabouts really.
If you took PTE and got the required grade, then the results are much faster. Normally within 2-3 days.