Had a similar experience on AC345 (YOW-YVR) on Sat. Oct 26. I was in 5D with Mr. R in 5G beside me on a 787, both of us SEs. On my side (port), the SD zig-zagged up and down the aisle taking meal orders by status, but she never crossed over to the starboard side. About 10 minutes after she finished taking everyone's order on port side, another FA started taking orders on starboard side, going row-by-row straight down the aisle. By the time she got to Mr. R she stated "We're all out of beef, but we still have the other choices". Luckily, his first choice was the fish dish, so no problem...but it was interesting watching them and trying to figure out what order "system" they were using.