well-timed vs seasonably

well-timed is an adjective but seasonably is not an adjective.

Word	Noun	Adjective	Verb	Adverb
well-timed	No	Yes	No	Yes
seasonably	No	No	No	Yes

As adverbs, well-timed and seasonably are synonyms defined as:

Other synonyms of well-timed include apropos, timely.

well-timed (adjective)	seasonably (adjective)
done or happening at the appropriate or proper time

well-timed (adverb)	seasonably (adverb)
at an opportune time	at an opportune time
	in accordance with the season