Technically, you can create a profile without the ECA report (by including 'dummy' information where you would need to enter the reference number and date of completion of the report) and then you can edit the profile once you get the real ECA report.
However, if you get an ITA during that time, you might have to decline it anyway and wait for a new one that comes after you get the ECA report, because you can't submit an eAPR (electronic application for permanent residence) with the dummy information - in fact, some people feel uncomfortable with just the fact that the ITA would have been received using the 'dummy' information. There's also always the risk that your ECA results could come back different than you expected (no one can be EXACTLY sure of how WES will assess their degree(s) until the report comes back, regardless of what the online predictive tool, or other people tell you).
It's a long and painful wait (I'm pretty sure the ECA report is what delays MOST people in submitting their EE profiles), but the best option might just be to wait to submit the profile until you have the official report in hand (this is one of the reason people like WES - they send you a soft copy of the report on the day that it's finished so that you don't necessarily have to wait on the mailed report - to be fair, I'm not sure if any of the other evaluation services does that though).
A score of 470 is nothing to sneeze at though. It's a fairly good chance that the CRS threshold for next few upcoming draws should (hopefully) stay low enough that you would get an ITA with a score of 470, even if you waited a month or two.