SPF record not being detected by gmail

I recently added SPF record to my server & it passes all the results required.

However sending email doesn't detect SPF record. The method I use to detect is whether gmail shows 'mailed-by'.

I use my own email server along with google's to include google apps features & this is the only spf record I have on my server.

SPF record is:

v=spf1 include:_spf.google.com ip4:X.X.X.X ~all

Is this because it takes some time to propagate the changes made in DNS file? Or is there something else I'm missing?

ISSUE EDITED

While seeing 'Show Original' menu from gmail, it gets me this:

Received-SPF: softfail (google.com: domain of transitioning noreply@example.com
does not designate 64.202.189.129 as permitted sender) client-ip=64.202.189.129;

Issue is the client ip mentioned above is changing in every email I receive even though I use SMTP relay from my server.

I talked with GoDaddy support & they said, ip will always change. There is no way it can use static ip for sending email.

What can be the possible solution to this?