Hi Krishna Eklarkar,

The online form for MH CET 2019 will be released probably in the third week of January 2019 and for the JEE Main 2019, as the JEE Mains helds twice a year i.e January and April.The exams to be held in January 2019 for that the registration has started from September 2018 and the last date to pay fees was October 2018.The registration for April JEE exam will commence from 8 Febuary 2019 to 7 March 2019. 

Hope this information helped to solve your queries.

JEE MAin April Session appplication form is expected to release on 8th Feb, 2019 & MHT application form is expected to release from third week of January, 2019.

You can stay tuned with the official websites or CAreers360 to get the updated information.

https://engineering.careers360.com/articles/jee-main-application-form

https://engineering.careers360.com/articles/mht-cet-application-form

Good Luck!