Here's my theory for what its worth:

After pondering over this delay last night I've come to the only conclusion that makes sense. Teck is very much interested in the property and region and I think it is very likely they set in motion this delay by requesting a double check of numbers, changes in mine plan etc. and even getting their own man involved in the mix.

ES knew what was going down and he phones Don Lindsay and they have a polite conversation about what's going down. ES complains to Don about the last minute changes and then Don tells him "Listen E we are very interested in acquiring you and we will agree to your price. However, we need a little more time to verify things with the new RE to make sure the numbers are good. We also need a little time to bring a partner on board. Things will happen but we need a little more time. Is that ok with you?"

ES - "Well our shareholders aren't going to like it but I think I can cook up something to make it look legitimate. How much time do you think you need?" Don " Well give us 2 months at least perhaps 4 to be safe." ES - "OK, you got it and I'll add a few more just to be on the safe side". Don "Thanks, ES, keep this under wraps. In a few months you'll all be very rich" ES - "Our shareholders won't like it but in the end that's what counts" Big grin as he hangs up.

IMHO, I think something like this may have went down and Teck will take us out before the BFS becomes public. My conspiracy theory for the day. Hope I'm right. :)