Before and after Patch 1.2 there have been numerous loading issues after the first sniper. The elevator to the balcony 20/21 would not load. Other times and more frequently an issue has been the with interior just outside the room with the second sniper as you progress through the mission. Here the interior simply refuses to load or is very buggy flashing in and out making the rest of the mission flat out unplayable. The only way I have found to work around this is to not use autosaved checkpoints beyond the start of the parade with the mini cutscene of V holding his/her hand up in the air. To my knowledge, this was not an issue at updates 1.5 or 1.6.