add fee-increase semantics to redemptions states doc
@@ -39,7 +39,7 @@ outstanding TBTC from the `Deposit` (counting any existing equity).
=== Flow reachable from
* Active
-** via `requestWithdrawal`* *Can exit flow to*
+** via `requestWithdrawal`*
=== Reachable exterior states
* `FRAUD_PRE_LIQUIDATION`
@@ -65,11 +65,14 @@ outstanding TBTC from the `Deposit` (counting any existing equity).
* *to*
** `AWAITING_WITHDRAWAL_PROOF`
-=== `changeWithdrawalFee`
-* *TODO*: should signers be able to call this after a certain amount of time?
-* Requester provides a new fee, requesting a new signature from the signers
+=== `increaseWithdrawalFee`
+* Explicitly allow a new signature with an increased fee. The fee may increased
+ in linear steps over time. The new fee must be explicitly authorized by the
+ contract, and the authorizing tx confirmed, before a new signature is
+ created.
* *access control*
-** deposit owner
+** Anyone
+*** after a timer
* *args*
** `uint256 _newFee`
* *reads*
@@ -113,8 +116,6 @@ outstanding TBTC from the `Deposit` (counting any existing equity).
== External Transitions
=== `requestWithdrawal` (inbound)
// TODO: link this elsewhere
-* *TODO*: Should the withdrawal transaction commit to a recent ethereum
- blockhash? This would prevent proof faking at the cost of some extra fees
* Deposit owner requests a withdrawal
* *access control*
** only deposit owner
