Take this scenario for instance
Electric terrain is up and Tapu Koko uturns out of Ferrothorn and brings in Hawlucha. Hawlucha has the seed and it disappears due to the terrain but on the switch, Ferrothorn hits Hawlucha with worry seed. Now, at this point, unburden already activated since seeds are consumed first before the opponent attacks, I think. However, after the seed is consumed, Hawlucha's ability is then replaced by insomnia due to worry seed
My question is, will Hawlucha still have the speed boost from unburden even tho worry seed replaced its ability?