Season 10 EU:

What	When
Season 10 [EU] Signups Open	9th of June (20:00 CEST)
Season 10 [EU] Signups Close	14th of July (23:59 CEST)
Season 10 [EU] Seeding	15th of July
Season 10 [EU] Round 1 starts	29th of July
Season 10 [EU] Last round (10) starts	30th of September
Season 10 [EU] Last date to play regular season games	11th of October
Season 10 [EU] Draw Show	13th of October
Season 10 [EU] Playoff Group Stage starts	14th of October
Season 10 [EU] Playoffs end	3rd of November

Season 3 NA:

What	When
Season 3 [NA] Signups Open	23rd of June - Announced on the Draw Show
Season 3 [NA] Signups Close	4th of August (11:59 pm EST/8:59 pm PST)
Season 3 [NA] Seeding	5th of August
Season 3 [NA] Round 1 starts	2nd of September
Season 3 [NA] Last round (8) starts	21 of October
Season 3 [NA] Last date to play regular season games	1st of November
Season 3 [NA] Draw Show	3rd of November
Season 3 [NA] Playoff Group Stage starts	4th of November
Season 3 [NA] Playoffs end	TBD