we check the sender view document:

https://developers.docusign.com/docs/esign-rest-api/reference/envelopes/envelopeviews/createsender/

for backButtonAction there are only previousPage and Redirect. We have set it to redirect, but there are still have “send later” button. when the  sender click ‘send later’, we send the envelope by API will failed.

we create the send view url and the backButtonAction as redirect, then open the url in another browser tab.

then click “send later”

it will send envelope failed as before, we create case with support team. now it can send success.

and we can query the scheduled workflow.

because as customer request, the envelope need send without send later, so we need call delete the workflow api to remove the schedule. So we hope we can disable this option for this button.

and another requirement is there are two signer, it will throw error place at least one field per recipient when click send later. but the customer want add requirement in the parameters of creadSend API like backButtonAction. let the sender must drag at least one signature for each signer. 

now we need query the recipient tabs and check whether each signer has signHereTabs and dateSignedTabs before send envelpe. we hope it can check when click continue, if not drag should notice the sender drag it. as the customer told the sender always only drag one signer, but not drag others.