Hey Susan, half long balls on the backhand side are certainly more difficult than the forehand as its harder to get the leverage and position to attack them with a topspin. So mostly it comes down to judgement on each ball, if it’s long enough to topspin usually thats the best option if you feel you can still make it a fairly positive shot and as you mentioned you will need to brush upwards more as with forehand half longs, but the more confident you get with these you will be able to add more forward motion too and get the bat angle closed to brush more forwards.
However if you feel you’re only able to brush upwards then most likely its too short and you will need to push back, I’d say pushing back a half long ball is much easier than flicking it (Unless the ballnis quite high over the net).
As long as you step in still and push through the ball nice and positive and get it deep, that’s not a big problem pushing back those half long balls. If it does come half long but higher over the net thats when you can come in and flick or even play a shorter topspin shot over the table. I hope that helps and we also have this backhand half long video which you might not have seen here which looks specifically at that shot:
