uint256 _numberOfNonReservesMinted = _storedTier.initialQuantity -
  _storedTier.remainingQuantity -
  _reserveTokensMinted;

uint256 _numerator = uint256(_numberOfNonReservesMinted * _storedTier.reservedRate);

uint256 _numberReservedTokensMintable = _numerator / JBConstants.MAX_RESERVED_RATE;

if (_numerator - JBConstants.MAX_RESERVED_RATE * _numberReservedTokensMintable > 0)
  ++_numberReservedTokensMintable;

return _numberReservedTokensMintable - _reserveTokensMinted;
+   if (_reserveTokensMinted > _numberReservedTokensMintable) {
+       return 0;
+   }

    return _numberReservedTokensMintable - _reserveTokensMinted;
