(2, HighZeroBytesDroppedBigSize(*sender_intended_htlc_amt_msat), required),
(4, HighZeroBytesDroppedBigSize(*cltv_expiry_height), required),
(8, payment_data, option),
(2, HighZeroBytesDroppedBigSize(*sender_intended_htlc_amt_msat), required),
(4, HighZeroBytesDroppedBigSize(*cltv_expiry_height), required),
(8, payment_data, option),