Following the instructions in this post: How to open HRMP channels between parachains? It lloks like the following instructions are required to open an HRMP channel:
- WithdrawAsset
- BuyExecution
- RefundSurplus
- DepositAsset
- Transact (to hold the encoded call for the request to open a channel)
But there's also the HrmpNewChannelOpenRequest instruction available to select. What's the use case for that instruction?