Whelan revealed he learned he had been released by Premier League-bound Aston Villa from two missed calls after landing in Dublin.
The 35-year-old, currently on international duty with the Republic of Ireland, was unavailable when manager Dean Smith called him days after the club's Sky Bet Championship play-off final victory over Derby.
Whelan said: “There was only one disappointment for me. I went away on the Tuesday with the family and when I landed back in here on Tuesday I had two missed calls, one from a journalist saying I'd been released and one from the manager to give him a call. “From that point of view it was disappointing, but something I expected to be honest."