My son and I paddled upstream from Poohbah Creek to Burntside a few years ago on or about 30 June.  If memory is correct, water levels were a bit higher than normal and it took us about 7 hours .  The only big struggle was up the swift to the second to last portage before Sturgeon.  I haven't been on the Maligne downriver from Poohbah Creek, but I think the upper Maligne has faster water.  You should be fine going upstream in mid-July unless there's been a daily deluge a few days prior.