Update a mailbox

sithbit mailbox update \
  [--keypair <keypair>] \
  [--default-postage <lamports>] \
  [--domain <name or address>] \
  [--skip-preflight]

Both --default-postage and --domain are optional — only the ones you supply are changed. For example, raising the default postage to price out a recent wave of spam:

sithbit mailbox update --default-postage 2000000000

…or moving to a different domain:

sithbit mailbox update --domain sithbit.net

The new domain must already be registered on-chain and active — updating a mailbox to reference an unregistered or deactivated domain is refused.

When a mailbox is no longer needed, see Appendix: Closing accounts for mailbox close and mailbox close-key.