As I mentioned in the other thread, AC is under no obligation to put you up in a hotel, provide meal vouchers, during IRROPS outside of their control (Weather, ATC delays etc). This for the most part, a North American standard.
If you are IN TRANSIT (i.e. connecting) during an IRROPs AC has shown leniency on taking care of you during IRROPs (but again are not under any obligation) with hotels/meal vouchers (I got helped during the great flood in July).
If you are originating/terminating pax you will not find them as helpful.
Again YMMV on what type of help you receive (hub vs spoke airport, status level, agen't mood etc). But the short end of it is, they are not obligated to provide additional compensation during IRROPs outside their control.
IRROPS inside their control (i.e mechanical, staffing issues) is a different matter and assistance/compensation is provided
depending on the delay.
You can find their official guidelines
here
DEFINITIONS
Controllable IROP
Any circumstance that Air Canada has direct control or influence over (mechanical situations and
situations not included in the uncontrollable IROP)
Uncontrollable IROP
Any circumstance outside of Air Canada’s control or influence. The delay codes are:
• Weather: WXD, WXL, WXR, WXS
• Work Disputes: SOW
• Air Traffic Control: SOA, EQW
• Security: SES
• Immigration: EQW
• Aircraft Damage: ANA
Note: That only unaccompanied/disabled pax are officially accomadated during uncotrollable IRROPs.