diff --git a/lib/byron/bench/Restore.hs b/lib/byron/bench/Restore.hs
index 4d8dbc281da..db506c7f97b 100644
--- a/lib/byron/bench/Restore.hs
+++ b/lib/byron/bench/Restore.hs
@@ -343,7 +343,7 @@ bench_restoration
         , WalletKey k
         , NFData s
         , Show s
-        , MaxSizeOf Address n k
+        , MaxSizeOf Address n ByronKey
         , PersistState s
         , PersistPrivateKey (k 'RootK)
         , NetworkDiscriminantVal n
diff --git a/lib/byron/test/unit/Cardano/Wallet/Byron/TransactionSpec.hs b/lib/byron/test/unit/Cardano/Wallet/Byron/TransactionSpec.hs
index 51e80e43758..d1c9154fc47 100644
--- a/lib/byron/test/unit/Cardano/Wallet/Byron/TransactionSpec.hs
+++ b/lib/byron/test/unit/Cardano/Wallet/Byron/TransactionSpec.hs
@@ -319,7 +319,7 @@ prop_rebalanceChangeOutputs sel onDangling = do
 propSizeEstimation
     :: forall n k.
        ( WalletKey k
-       , MaxSizeOf Address n k
+       , MaxSizeOf Address n ByronKey
        )
     => ProtocolMagic
     -> Gen CoinSelection
@@ -334,13 +334,16 @@ propSizeEstimation pm genSel genChngAddrs =
         cbor = fromCoinSelection sel chngAddrs
         size = fromIntegral $ BS.length $ CBOR.toStrictByteString cbor
 
+        -- As we have
+        -- maxSizeOf Icarus w/ Mainnet = 43
+        -- maxSizeOf Random w/ Mainnet = 76
         -- We always go for the higher bound for change address payload's size,
-        -- so, we may end up with up to 12 extra bytes per change address in our
+        -- so, we may end up with up to 33 extra bytes per change address in our
         -- estimation.
         -- For Icarus addresses, we can be as good as 4 bytes per change address
         -- because there's no variance due to the derivation path encoded as
         -- attributes (this only happens on random addresses).
-        margin = 12 * fromIntegral (length $ change sel)
+        margin = 33 * fromIntegral (length $ change sel)
         realSizeSup = Quantity (size + margin)
         realSizeInf = Quantity size
     in
@@ -510,7 +513,7 @@ xprv seed =
 goldenTestSignedTx
     :: forall (n :: NetworkDiscriminant) k.
         ( k ~ IcarusKey
-        , MaxSizeOf Address n k
+        , MaxSizeOf Address n ByronKey
         , PaymentAddress n k
         )
     => Proxy n