You won't know unless you try. Leave a check strip and let's us know how it turns out.
Jump to conclusions this field hasn't had canola since 2009, I also said I might do lance as well as proline, when the crop was fertilized for corn and ended up being seeded to canola and looks as good as it does and being on bean ground I'd like to protect it and not let disease take over.Spraying same fungicide twice? EEEK!
In a healthy 4 year rotation with canola that is the same resistance pressure as 8 years of proper stewardship.
But since most farmers are doing a 2 year, well you can do the math....