Citizenship eligibility criteria and residence calculator are contradicting

Context:
I will be completing living in Australia in total, including overseas trips, on 19/04/2021. I am planning to travel overseas next month i.e. 19/02/2021 for lets say 6-9 months as I don’t know when I will be able to return due to covid. I think I will meet the residence requirement. I am looking from our experts here to confirm if my findings and understanding is correct or am I missing something?

Under Step 3 on the website, it says:
You can apply and pay online whether you are in Australia or overseas.

Under eligibility tab, residence requirement is:
At the time you apply you must have been:

• living in Australia on a valid visa for the past 4 years
• a permanent resident or eligible New Zealand citizen for the past 12 months
• away from Australia for no more than 12 months in total in the past 4 years, including no more than 90 days in total in the past 12 months

I haven’t travelled in the past one year. So I will meet 90 days rule. Now even if I travel in February month and I am getting eligible in April month, then also I will meet 90 days rule.

Questions:
1. If I use residence calculator on the website, Intended application date – 19/04/2021, then:
a) It says ‘Residence requirement is met’ if I don’t include planned travel this year starting from 19/02/2021.
b) It says ‘Residence requirement is met’ if I travel on 19/02/2021 and return back on 18/04/2021 i.e. one day before I complete 4 years in total in Australia
c) If I include travel from19/02/2021 to 20/04/2021 i.e. one day after my intended application date, it doesn’t let me save the date detail and it throws validation error ‘Lodgement Date cannot occur during trip.’ See below image. Now this is totally contradicting as per the info mentioned under Step 3 above that ‘You can apply and pay online whether you are in Australia or overseas.‘ Am I right? I think this is an issue with the calculator which I should ignore?

View attachment 98979

2. “living in Australia on a valid visa for the past 4 years” -> If I continue to stay in Australia till 19/04/2021, then I meet this criteria. If I travel overseas on 19/02/2021 and return after 6-9 months, do I still meet this criteria and other residence requirement criteria’s as per you? I think I would meet this criteria as residence calculator would not have said ‘Residence requirement is met’ for my scenario b mentioned above if that was not the case.

Please let me know your thoughts/expert opinions as it will be really useful to me in deciding my start date of the trip. I tried calling department of home affairs and they give really generic responses and don’t want to listen to my scenario. They mentioned if you meet eligibility criteria, then you can apply. And I am like, what seriously.