Currency forward negative roll yield (buy low sell high)

Given the data in the table, the roll yield on this hedge at the forward contracts’ maturity date is most likely to be:

  1. L3V3R17-280 zero.
  2. L3V3R17-281 negative.
  3. L3V3R17-282 positive.

B is correct. To implement the hedge, Brixworth & St. Ives must sell MXN against the GBP, or equivalently, buy GBP (the base currency in the P/B quote) against the MXN. The base currency is selling forward at a premium, and—all else equal—its price would “roll down the curve” as contract maturity approached. Having to settle the forward contract means then selling the GBP spot at a lower price. Buying high and selling low will define a negative roll yield. Moreover, the GBP has depreciated against the MXN, because the MXN/GBP spot rate declined between one month ago and now, which will also add to the negative roll yield.

(Institute 388)

Institute, CFA. 2020 CFA Program Curriculum Level III Volume 3 . CFA Institute, 08/2019. VitalBook file.

The citation provided is a guideline. Please check each citation for accuracy before use.

My question is what numbers i should be looking at to know this is a buy low sell high?