I would like to know how to handle custom fields in Estimate Shipping and Tax block with help of this answer. I updated block with custom field(radio button) but I'm not sure how to handle custom field as extension attribute.
I tried with this stack exchange answer, which shows how to handle custom field in shipping information. but it doesn't help me, as I'm not sure which actions should be used for Estimation and I don't find any documentation on handling new field in Estimate Shipping and Tax block.
Can some one guide me on this ?