I spend good amount of time for searching replacement of my current ride in last three weeks. Went to Toyota Garden & Walton as well couple of times. Yaris is selling at good pace, not like Corolla but it is selling.
In used car markets, situation is very much different. The dealer mafia is apparently united against it for some reason. 0 resale and attraction for Yaris in used car market. They created huge demand for Gli which resulted is sky rocketed prices of GLi, The Xli variant is quite slow though finally after ruling Pakistan for decades.
I was potential buyer and wanted a new car in 03 mill but Yaris backseat leg space and build quality was big turn off for me. One strange incident happen, I called the owner of a advertised Yaris 1.5 Ative x 7200 KM driven, He said I sold my car to my friend on instalment and also said "Bhai Jaan sincere advice, If you have ever kept Corolla, never go for Yaris".
My own guess is: Corolla (Gli & Xli) are gone for good, eventually Yaris will take their place, it's just matter of time. But in mean time dealers and showrooms will mint good money selling leftover and used Corolla.