After and before application is submitted--
[1] Each application is different but processing time will also depend how organized and non-ambiguous application is. It's applicant's duty to provide ALL required documents with following the required details. IRCC Officer should not struggle a lot while reviewing your documents.
[2] Do your homework before sending the application to avoid any basic mistakes that will result into refusal. Adding additional/supporting documents is good idea but those should be well organized to avoid any confusion.
[3] Once submitted, follow other AOR forums and decide your strategy when to contact IRCC ( via a web-form/ calling/ GCMS notes)
[4] Applicant can order GCMS note every month but It makes sense to order those after specific interval of months and knowing your current status.
[5] Decode comments/observation seen on GCMS notes and take action pro-actively.
Example: If one of the document did not have job duties, you can submit a new letter. You can save your application being pro-active.
[6] If passport is renewed or child is born, IRCC should be notified with the new information. Web-form is best tool to clarify and know your steps.
[7] Do not rely on online profile status or progress %. It's totally useless. I will write separate post to explain why.
Sometimes customer call do not provide the right information or simply deny to share info. So, In order to know exact status, try this [1] Call IRCC and then wait for at least 2 weeks and [2] Submit another web-form for status. Keep in mind, the web-form status wins.