At the moment it’s impossible to edit the pie holdings while there is an order pending (either buying or selling).
It’s also impossible to have two different kind of orders pending at the same time, unless using the default rebalancing function.
There are times when I want to manually rebalance some part of the pie only and I can not sent a buy order and a sell order at the same time.
During market hours it’s no big deal since as soon as the first order fills I can enter the second one, but out of market hours it can be frustrating to only send the sell order and remember to send the buy order hours later.