You replied to a post that was meant for someone elsemtina said:1.Yes My father was working with CRPF and retired in 2002.
2.They need to visit less than 6 months.
3.Property details of both my mother and father including house is only submitted. and my fathers pension details.
4. they haven't travelled anywhere till now.
Based on your previous post, IRCC is running background checks on your dad (particularly his employment). Quite honestly, I would not be too optimistic about him coming to Canada in April. You can try sending a CSE to the relevant visa office
There's a thread by poster 'Prayas' where people with similar backgrounds (defense though) have been waiting since August 2016. Last week, one of them got the TRV