Here my expected times for the checkpoints:
5K   21:34
10K 43:03
15K 1:04:45
20K 1:26:41
Half 1:31:24
25K 1:48:26
30K 2:10:24
35K 2:32:22
40K 2:53:56
Finish 3:03:30
		
		
	 
 Tough for me to predict my time, given my training was less than half of my last Boston cycle.  But I have more marathon experience, now, and know how to use HR as a guide.  Using Steve's HM/marathon formulas (HMx2.1 for elites; roughly HMx2.2 or 2.25 for mortals), I'd speculate a 3:45-3:50.  I want a 3:40 Boston PR; I'd live with a 3:55 to requalify.  Once I requalify, an early goal for 2016 is to finish top 10% of my new AG at Boston'16, which is achievable.  I'll try to push the edge with a 3:40 in mind.   
Bib #18044.
3:40 pacing ....3:50 pacing
5K:       25:30 .....    26:43
10K:     51:22 .....    53:49
15K:  1:17:16 ..... 1:20:57
20K:  1:43:14 ..... 1:48:09
Half:  1:48:54 ..... 1:54:06
25K:  2:09:04 ..... 2:15:13
30K:  2:35:16 ..... 2:42:40
35K:  3:01:52 ..... 3:10:23
40K:  3:28:15 ..... 3:37:48
End:  3:40:00 ..... 3:50:00